Social wasps – including hornets, yellowjackets, and paper wasps – have that name because they live in colonies, not because we like to have them around. Their paper nests are made from a combination of plant fibers and wasp saliva and usually are found hanging under building eaves or tree branches. A mature colony contains from 200 to as many as 15,000 individuals. The numbers peak in late summer, the time when we find these pests buzzing around our patios, picnic tables, and garbage cans.
In addition to being annoying, these pests (particularly yellowjackets) can become aggressive in protecting their nests and inflict painful stings. If you are stung, apply a cold compress or ice pack to the swollen area. Call your doctor if a severe reaction such as extreme swelling, dizziness, or difficulty in breathing develops.
To clear an area of these pests, you must eliminate their nests:
- Spray the nests at dusk or during the night with wasp killer, which comes in an aerosol can with a jet spray to reach nests up to 20 feet above ground.
- Hold the can upright at arm’s length. Spray any visible openings first and then soak the remainder of the nest. The foaming action will trap insects in the nest.
- Insects returning to the nest will be killed, so wait at least 24 hours before removing and disposing of the treated nest.